What is Nano Technology?

Description

For industrial purposes, the use of matter on an atomic, molecular and supramolecular scale is recognized as Nano Technology. With a huge range of applications, the nanotechnology might be capable to create many new materials and devices, for example in Nano medicine, Nano electronics, bio materials energy production, and consumer products. The nanotechnology instead increases numerous of the same issues as any new technology, including worries about the toxicity and environmental impact of nanomaterial, and their possible effects on global economics, in addition to speculation about many end of the world scenarios.

Definition

The research and development initiative named (NNI) National Nanotechnology Initiative defines nanotechnology as" the handling of matter at any rate one dimension sized from one to hundred nanometers". Through defined nanotechnology by size is clearly comprehensive as including fields of science as varied as organic chemistry, surface science, molecular biology, energy storage, semiconductor physics, engineering, micro fabrication, and molecular engineering.

Important concepts

Nanotechnology is the manufacturing of useful systems at the molecular scale. The more advanced and current work concepts are being covered by it. Nanotechnology mentions to the projected capability to build items from the bottom up in its original sense. The techniques and tools are being developed today to make whole, high performance products.

One (nm) nanometer is one billionth. Normal carbon to carbon bond lengths, or the positioning between these atoms in a molecule by contrast are in the range 0.12 to 0.15 nm, and a DNA double-helix has a diameter around 2 nm. The minimum cellular life-forms on the other hand, the bacteria of the genus Mycoplasma, are around 200 nm in length. Nanotechnology by bond is taken as the scale range 1~100 nm following the definition used by the National Nanotechnology Initiative in the US. By the size of atoms the lower limit is set meanwhile nanotechnology must build its devices from atoms and molecules.

Two key methodologies are used in nanotechnology. Materials and devices are built from molecular components which collect themselves chemically by principles of molecular recognition in the bottom-up approach. In the top-down approach, nano-objects are built from greater objects without atomic-level control. Regions of physics for instance Nano mechanics, Nano electronics, Nano photonics and nanoionics have changed during the last few eras to deliver a basic scientific foundation of nanotechnology.

Materials perspective (Higher to lesser)

By way of the size of the system decreases some phenomena become marked. These contain statistical mechanical effects. For example the quantum size effect where the electronic properties of solids are changed with great falls in particle size. This effect does not derive into play by going from macro to micro dimensions.

Molecular perspective (Simple to Complex)

Modern synthetic chemistry has touched the point where it is possible to prepare small molecules to nearly any structure. These approaches are used nowadays to making a extensive change of useful chemicals for instance pharmaceuticals or commercial polymers. This facility increases the question of extending this kind of control to the next-larger level, seeking methods to assemble these single molecules into supramolecular gatherings containing of many molecules agreed in a well-defined manner.

Long-term view (Molecular nanotechnology)

Molecular nanotechnology describes engineered Nano systems working on the molecular scale. This is particularly related with the molecular assembler. The molecular assembler is a machine which may create a wanted structure or device atom-by-atom by means of the principles of mechanosynthesis. Engineering in the setting of productive nanosystems is not connected to, and must be obviously eminent from, the conventional technologies used to manufacture nanomaterials for example carbon nanotubes and nanoparticles.

It mentioned to a future manufacturing technology founded on molecular machine systems when the term "nanotechnology" was independently created and promoted by Eric Drexler. The evidence was that molecular scale biological analogies of traditional machine components demonstrated molecular machines were possible: by the countless examples found in biology, it is recognized that refined, stochastically optimised biological machines may be produced.

Present-day Research

Nanomaterials

The nanomaterial field comprises subfields that develop having high-class properties rising from their Nano scale dimensions. Nano scale materials also can be used for majority applications; most current commercial applications of nanotechnology are of this flavor. Expansion has been finalized by means of these materials for medical applications. Nano scale materials like Nano pillars are sometimes utilized in solar cells which combat the value of traditional silicon solar cells. Development of applications incorporating semiconductor nanoparticles to be utilized in subsequent generation of products, like display technology, lighting, solar cells and biological imaging; see quantum dots. New application of nanomaterial contains a variety of biomedical applications, like tissue engineering, drug delivery, and biosensors.

Bottom-up approaches

These seek to rearrange smaller components into more complex assemblies. The DNA nanotechnology uses the specificity of Watson–Crick base pairing to build well-defined structures out of DNA and other nucleic acids. Methods from the sector of "classical" chemical synthesis also aim at designing molecules with well-defined shape.

Molecular self-assembly more generally seeks to use concepts of supramolecular chemistry, and molecular recognition especially, to cause single-molecule components to automatically arrange themselves into some useful conformation.

Atomic force microscope tips are often used as a Nano scale "write head" to deposit a chemical upon a surface during a desired pattern during a process called dip pen nanolithography. This system fits into the larger subfield of nanolithography.

Molecular Beam Epitaxy permits for bottom up assemblies of materials most particularly semiconductor materials commonly utilized in chip and computing applications, stacks, gating, and nanowire lasers.

Top-down approaches

These pursue to mark smaller devices by using greater ones to direct their assembly.

Many technologies that sloped from conventional solid-state silicon methods for fabricating microprocessors are now capable of making features smaller than 100 nm. Solid-state techniques also can be wont to create devices referred to as nanoelectromechanical systems or NEMS, which are associated with microelectromechanical systems or MEMS. Focused ion beams can directly remove material, or maybe deposit material when suitable precursor gasses are applied at an equivalent time. for instance, this system is employed routinely to make sub-100 nm sections of fabric for analysis in Transmission microscopy.

Functional approaches

These seek to develop components of a desired functionality without reference to how they could be assembled. Magnetic assembly for the synthesis of anisotropic super paramagnetic materials like recently presented magnetic Nano chains. These could then be used as single-molecule components during a Nano electronic device.

Bio nanotechnology is that the use of bio-molecules for applications in nanotechnology, including use of viruses and lipid assemblies. Nano cellulose may be a potential bulk-scale application.

Speculative

These subfields seek to anticipate what inventions nanotechnology might yield, or plan to propose an agenda along which inquiry might progress. These often take a big-picture view of nanotechnology, with more emphasis on its societal implications than the small print of how such inventions could actually be created.

Molecular nanotechnology may be a proposed approach which involves manipulating single molecules in finely controlled, deterministic ways. This is often more theoretical than the opposite sub fields, and lots of its proposed techniques are beyond current capabilities.

Dimensionality in nano materials

Nano materials are often classified in 0D, 1D, 2D and 3D nano materials. The dimensionality play a serious role in determining the characteristic of nano-materials including physical, chemical and biological characteristics. With the decrease in dimensionality, a rise in surface-to-volume ratio is observed. This indicates that smaller dimensional nano materials have higher area compared to 3D nano-materials. Recently, two dimensional (2D) nano materials are extensively investigated for electronic, biomedical, drug delivery and biosensor applications.

Mansoor Ahmed Chemical Engineer,Web developer